Generally, as the multimedia society is developing rapidly, the demands for a large-scale display screen and high image quality thereof has risen. Recently, it becomes important to implement natural colors smoothly in addition to high resolution.
In order to implement perfect natural colors, it is essential to use such a light source of high color purity as a laser. And, one of devices for implementing images using laser is a laser projection display device using a light scanner.
The laser projection display device implements images in a manner of scanning a light, which is generated from a laser light source, on a screen using a light scanner.
In this case, a driving speed of the light scanner should be high to implement images of high resolution.
In particular, the high driving speed of the light scanner means that a driving angle of the light scanner should be large.
The light scanner tends to have an increasing driving angle if a drive signal has a specific frequency. And, the specific frequency of the drive signal for increasing the driving angle of the light scanner is called a resonant frequency.
Hence, if a drive signal corresponds to a resonant frequency, a light scanner has a largest driving angle and enables its high-speed driving.
Yet, since a light scanner has a resonant frequency that varies due to manufacturing deviations on process, there are many difficulties in generating a drive signal corresponding to a resonant frequency by considering these manufacturing deviations.
Moreover, the resonant frequency of the light scanner may vary due to intensity of light incident on the light scanner in addition to the manufacturing deviations on process.
In particular, as intensity of light incident on a light scanner is unit uniform, a temperature of the light scanner varies according to a time. And, a resonant frequency of the light scanner varies according to the time, correspondingly.
However, according to a related art, a light scanner has been driven by generating vertical and horizontal drive signals from a standard video format without considering a resonant frequency of a light scanner.
Hence, the light scanner fails to be driven in correspondence with the inputted vertical and horizontal drive signals due to the varying resonant frequency but generates errors from being driven.
The driving errors of the light scanner cause a problem of changing a left/right portion of a displayed image in part, a problem of changing a top/bottom portion of the displayed image in part, and/or a problem of making an overall image displayed very small.
Therefore, the demand for developing a system capable of compensating for inputted horizontal and vertical sync signals in consideration of a resonant frequency of a light scanner is rising.